DES MOINES, Iowa – Iowa could make or break a Democratic candidate on Thursday.

The state has unparalleled influence, even after several larger states moved up their contests,doing little more than compressing the calendar into a five-week sprint to the multistate primary Feb. 5 – strengthening Iowa’s position as the leadoff caucus state.

Hillary Rodham Clinton, Barack Obama and John Edwards are locked in a tight contest in Iowa just days before voters attend their precinct caucuses on Thursday. And while all three have strong organizations in other early states, the best-laid plans in those places could come apart depending on what happens in Iowa.

Only Obama and Clinton have raised enough cash to be sure of being competitive through Feb. 5 and beyond. Edwards has agreed to accept federal matching funds, constraining the amount of spending allowed in each state.

Trailing in polls, Bill Richardson, Joe Biden and Chris Dodd have also focused their resources in Iowa in hopes of an upset.

Here’s a look at what to expect in the next several weeks:

IOWA

Jan 3 (45 pledged delegates)

All six major Democratic candidates will blitz the state before Thursday. Hundreds of staff and volunteers will flood likely caucus goers with mail, visits and phone calls. TV airwaves have been saturated for weeks with ads.

Clinton, who has struggled in Iowa despite leading in national polls, has the most riding on the outcome. A win could fuel momentum for the former first lady, while a loss, particularly to Obama, would shatter the notion of inevitability she has tried to project.

The New York senator is barnstorming the state and has deployed dozens of surrogates including her husband, former President Bill Clinton.

Obama and Edwards are competing to be the strongest “anti-Clinton” candidate. Edwards’ base lies with caucus goers who were with him when he ran for president in 2004. Obama and Clinton are competing for newcomers: hers, mostly older and female; his, younger and male.

Spending by outside groups has added a new dimension. Obama’s advisers fret that he is being hurt by the influx of spending on the other candidates’ behalf.

NEW HAMPSHIRE

Jan. 8 (22 pledged delegates)

The candidates are reinforcing their organizations in New Hampshire to prepare for whatever verdict Iowa delivers.

The Clinton campaign scrambled as her New Hampshire lead faded. The situation was further roiled when a prominent supporter, Bill Shaheen, stepped down as a campaign co-chairman after raising concerns about Obama’s teen drug use. But Clinton has strong ties to the state thanks to her husband’s 1992 and 1996 campaigns.

Obama strategists say the key lies with independents who can vote in either political party’s primary and oppose the Iraq war.

The Edwards campaign says its volunteers have knocked on 235,000 doors in the state.

MICHIGAN

Jan. 15 (128 pledged delegates; national party says the state will lose them all)

The Democratic candidates have agreed not to compete in Michigan because the state moved the date of its primary in violation of party rules.

NEVADA

Jan. 19 (25 pledged delegates)

Nevada will be the first state with delegates at stake after the New Hampshire primary and could play an important role if the race is still competitive.

While party leaders estimate only about 40,000 voters will take part in Nevada’s caucuses, all the major candidates have spent considerable resources in hopes of securing a win among a Western, heavily Hispanic electorate.

The campaigns are all counting on momentum and strong organization to fuel their efforts. The candidates are basing their organization on an Iowa caucus model.

Richardson has spent more time here than any other candidate, hoping to parlay his Hispanic heritage and proximity as governor of neighboring New Mexico into a strong showing.

All the campaigns are vigorously competing for the backing of the Culinary Union, which represents some 60,000 service workers along the Las Vegas strip.

SOUTH CAROLINA

Jan. 26 (45 pledged delegates)

The three top-tier candidates have grounds to lay claim to South Carolina – Obama and Clinton because of their popularity among black voters, Edwards because he was born in the state and won its primary four years ago.

Clinton and Obama have strong organizations in the state and have begun sustained television advertising recently. Both have made a concerted effort to woo black voters, who were 50 percent of primary voters in the state last time; they’ve run ads on black radio and sought endorsements from community leaders and black legislators.

Edwards has run television ads since November and has made more campaign visits than Obama or Clinton. Polls show him running a distant third but slowly gaining ground.

FLORIDA

Jan. 29 (185 pledged delegates, may be lost)

Like Michigan, Florida has been penalized for moving its primary in violation of party rules. The national party has stripped the state of its delegates, and the candidates have pledged not to campaign in the state, although they have made several fundraising visits.

MEGA TUESDAY

Feb. 5 (At least 20 states and 2,075 pledged delegates)

Contests from Connecticut to California on this day could end up determining the Democratic nominee.

Clinton has seen her lead diminish somewhat in California, whose 441 delegates represent the day’s largest prize. But the campaign is running generally strong and targeting absentee voters who can begin casting ballots Jan. 8.

Obama has bolstered efforts in California, and polls show him running strong in Georgia and Missouri. He’s strongest in his home state of Illinois, while Clinton is dominant in her home state of New York and in nearby New Jersey.